I bought a new iphone 4 but it still has service from old user?

Hi! I bought an iphone off this guy. His service is still on it, and he told me to cancel it and put my phone service on it. The acount isn't in his name and he doesn't know the information. I know you probably think it was stolen, but it wasn't. Is there any way i can cancel it on my own? Like reset the phone or something and make it brand new?

You could probably take it to the nearest Apple Store or the provider he had on it and they will tell you what you need to know. Try resetting the phone first or clearing the data and see if that helps. If not, then just try what I suggested in the beginning.

Only the account holder can cancel the account on it. From the sounds of it, this is a CDMA phone for Sprint or Verizon because normally on an iPhone 4, you would just switch SIM cards if it was a GSM carrier like T-Mobile or AT&T. But since CDMA uses ESN #s for service, if the account holder does not pay the bill (let it lapse) or does report it lost or stolen, you won't be able to use the phone on Sprint or Verizon anymore because the ESN will be marked bad. So you better find out who is the account holder (assuming the phone isn't lost or stolen) and get that person to cancel the account right away.

Just remove his sim card out of the phone and cut it. Then get your aim card and put in the phone.